Not applicable.
Not applicable
This invention relates to furniture polishes. In particular, it relates to biliquid foam dispersions useful as furniture polishes, and methods of polishing furniture using them.
In U.S. Pat. No. 3,965,518 it was proposed to apply (via a wipe) a furniture polish containing, among other things, water, mineral oil, silicon oil, nonionic surfactant and/or anionic surfactant, preservative and pH adjustor, in an emulsion form. However, emulsions tend to require relatively high levels of surfactant to render them stable.
As the level of surfactant decreases, the stability of the emulsion often correspondingly decreases, leading to a need to shake the product before use. Should a consumer forget to shake the product, the resulting spray will have more of certain ingredients than desired while the residue in the container will similarly have skewed chemistry. This can lead to consumer dissatisfaction with the product as the person using the product the second time may not be the one who forgot to shake prior to the first usage. Also, the surfactants used in high concentration may not have optimal characteristics with respect to residues left on the furniture.
Moreover, some emulsions tend to interfere with the effectiveness of some antimicrobial agents. Antimicrobial agents are important both with respect to the storage of the polish and with respect to the surfaces being treated. In this regard, there is a recent trend towards including antimicrobials in products such that the surfaces being treated also have antimicrobial properties.
Also, silicone oils are particularly desirable ingredients in furniture polishes. They provide a highly desirable visual appearance. However, conventional emulsions tend to have stability and/or solubility problems when they contain silicone oils, absent the use of a polar hydrocarbon solvent. Many polar hydrocarbon solvents (especially alcohols) can be undesirable due to environmental or flammability concerns, or their effect on some furniture surfaces.
As also noted in U.S. Pat. No. 3,965,518, furniture polishes have been previously formulated in a variety of forms, such as pastes, lotions, creams, and emulsions sprayed from a pressurized container. When a furniture polish is delivered via an aerosol, an aerosol can is typically charged with emulsified polish liquid and also a propellant which is typically a hydrocarbon gas such as butane, propane, isobutane, isopropane, or mixtures thereof. The polish is sprayed from the can onto the surface to be treated, sometimes after shaking the can to re-establish the uniformity of the emulsion. See generally U.S. Pat. No. 4,354,871 for its discussion of aerosol emulsion furniture polishes.
In unrelated work the art has developed oil-in-water dispersions known as biliquid foams. In these dispersions the oil is present in discrete droplets surrounded by a first surfactant. The remaining water has dissolved in it a second surfactant. The second surfactant migrates to the surfactant-coated surface of the oil to create at least some drops (preferably most oil drops) surrounded by a bilayer of surfactant. See generally U.S. Pat. Nos. 4,486,333 and 6,312,760. See also F. Sebba, Biliquid Foams-A Preliminary Report, 40 J. Colloid. Interface Sci. 468-474 (1972); O. Sonneville-Aubrun et al., Surfactant Films In Biliquid Foams, 16 Langmuir 1566-1579 (2000) and a Disperse Technologies Limited 1998 technical presentation entitled xe2x80x9cAdvanced Topical Dispersion Technologyxe2x80x9d.
Early versions of these foams suffered from significant instability. However, U.S. Pat. No. 6,165,479 taught that adding a viscosity modifier/thickener to such foams can markedly increase the stability of the foam. However, this patent was largely focused on formulating cosmetics, and thus did not address design/formulation problems in creating furniture polishes.
Thus, a need still exists for improved furniture polishes, particularly those containing polysiloxanes.
In one form the invention provides a furniture polish in the form of a dispersion comprising a biliquid foam having a thickener selected from the group consisting of carbomers, colloidal polymers and gums. The dispersion, apart from the thickener, has at least 0.01% by weight of an oil selected from the group consisting of polysiloxanes and hydrocarbon oils, between 0.0001% and 2% by weight of surfactant, and at least 10% by weight of water. The dispersion, apart from the thickener, will typically have between 0.0001% and 2% by weight of an essentially non-polar surfactant (e.g. a nonionic surfactant), and between 0.0001% and 2% by weight of a more polar surfactant selected from the group consisting of anionic surfactants, cationic surfactants and amphoteric surfactants.
In a particularly preferred form, the dispersion, apart from the thickener, has at least 1% by weight mineral oil, and at least 1% by weight of polysiloxane. High levels of mineral oil and polysiloxane (especially together totaling over ten percent of the dispersion apart from the thickener) that had previously made formulating emulsions that contain them particularly difficult.
The formulations of the present invention do not need to have polar volatile cosolvents to achieve stability, even when polysiloxanes are present. This may have certain advantages in jurisdictions that are particularly environmentally conscious. It may also have advantages where the treating material is applied to certain sensitive surfaces.
For example, the mixture can be essentially free of organic solvents having a volatility of greater than 0.1 mm/Hg at 20xc2x0 C. Alternatively, the mixture can be essentially free of organic solvents having a volatility of greater than 0.13 mm/Hg at 20xc2x0 C. Further, the mixture can be.essentially alcohol free.
In another aspect the invention provides a method of polishing a. piece of furniture (e.g. a table, a dresser, a chair, a bookcase, etc.). One obtains an aerosol container containing a liquid polish of the present invention. The polish is in the form of a dispersion, the dispersion having an oil-based biliquid foam and a thickener selected from the group consisting of carbomers, colloidal polymers and gums. The dispersion, apart from the thickener, has at least 1% by weight of silicone oil, at least 1% by weight of mineral oil, between 0.0001% and 2% by weight of nonionic surfactant, between 0.0001% and 2% by weight of a surfactant selected from the group consisting of anionic surfactants, cationic surfactants and amphoteric surfactants, and at least 10% by weight of water.
One sprays the polish against the piece of furniture. Polishes of this type are best used if one rubs the polish in with a cloth or the like. The cloth may contain mixtures of cellulosic fibers with other natural or synthetic fibers (e.g. cotton or wool), or be entirely formed of natural or synthetic fibers (e.g. rayon, polyamide fibers, acrylonitrile fibers, polyester fibers, vinyl fibers, protein fibers, fluorocarbon fibers, dinitrile fibers, etc.). A clothing rag is a typically suitable cloth.
The dispersion should include a thickener/viscosity modifier such as carbomers (such as a polymer of acrylic acid that has been cross-linked with a polyfunctional agent), colloidal polymers, or gums at a concentration of between 0.05 and 2%, preferably between 0.05 and 0.5%. Other examples are alginate gums or their salts, guar gum, locust bean gum, xanthane gum, gum acacia, gelatin, hydroxymethylcellulose, hydroxyethyl-cellulose, hydroxypropylcellulose, carboxymethylcellulose, salts of these compounds, bentonites, magnesium aluminum silicates, and glyceryl polymethacrylates and their dispersions in glycols, and mixtures thereof. The most preferred thickener for our furniture polishing wipes is a salt of a cross-linked polymer of acrylic acid known as Carbopol(copyright) Ultrez 5 (which is available from B.F. Goodrich). This thickener is a polymer of acrylic acid cross-linked with allylpentaerythritol.
The dispersion may also have other optional ingredients. For example, there may be a preservative such as Kathon(copyright) ICG which is available from Rohm and Haas, appropriately pH adjusted with sodium hydroxide.
There may also be scratch cover colorants, fragrances and other additives as are conventional in the furniture polishing field when the product is a furniture polish. See generally U.S. Pat. No. 5,849,838.
A wide variety of nonionic surfactants appear to be used for the purposes of the present invention. We particularly prefer the use of Laureth-4 (polyethylene glycol ether of lauryl alcohol). However, one could instead use an alkanolamide, an ester of a polyhydric alcohol (for example an ester of an ethylene, diethylene or propylene glycol, or glycerol or a polyglycerol, or sorbitan, glucose or sucrose), a polyoxyethylene or polyoxypropylene derivative of an alcohol, amide or ester, or a polyoxyethylene/polyoxypropylene block copolymer, or a suitable compatible mixture thereof.
The other surfactant (when, as is typical, two are used) can be selected from a wide variety of more polar surfactants. We prefer the anionic surfactant sodium lauryl ether sulphate. However, numerous other anionics should be suitable. Examples are acyl-lactate, N-acylsarcosinate, alkyl-carboxylate (either mono- or polyvalent), alkyl ether carboxylate, N-alkyl-glutamate, fatty acid-peptide condensate, phosphated ethoxylated alcohol, alkyl sulphate, ethoxylated alkyl sulphate, alpha-olefin sulphonate and ester-linked sulphonate.
The other surfactant may also be a cationic surfactant, an example of which is an amidoamine. Alternatively, the other surfactant might be an amphoteric such as acylaminoacid, an N-substituted alkylamine, an N-alkyl-xcex2-aminopropionate, an N-alkylbetaine, an alkylimidazoline and a sulphobetaine.
The preferred polysiloxanes are dimethylpolysiloxanes. However, other silicones can also be used. Further, a wide variety of hydrocarbon oils should be suitable. Preferred viscosity ranges are between 50 cts and 5,000 cts.
The present invention provides furniture polishes that are highly stable, are suitable to have incorporated therein propellants and polysiloxanes, and do not recuire high levels of volatile or organic components.
While preferred embodiments have been discussed above and will be discussed below, it should be appreciated that these are merely examples of the invention. For a more complete appreciation of the full scope of the invention the claims should be reviewed.